Brolucizumab Superior in Preserving Visual Acuity in Proliferative Diabetic Retinopathy

Patients with proliferative diabetic retinopathy (PDR) had more success in preserving visual acuity when taking brolucizumab when compared with panretinal laser photocoagulation (PRP) monotherapy, according to a new study published in JAMA Ophthalmology.¹ The study provides a glimpse at an alternative treatment method for patients with PDR.

Diabetic retinopathy, a leading cause of preventable blindness in adults of working age, affects about 22% of all people with diabetes in the world. PRP is the main form of therapy for patients with PDR and has been effective in the past, despite complications that are reported, such as choroidal effusions.² Brolucizumab is a single-chain antibody fragment that is able to penetrate to the retinal pigment epithelium with minimal systemic exposure. This study aimed to compare the efficacy of brolucizumab compared with PRP over 54 weeks in patients with PDR who had not been previously treated with PRP and did not have concurrent DME.¹

The CONDOR study is a phase 3 study lasting 96 weeks, taking place across 152 sites in 16 different countries: the US, Argentina, Australia, Brazil, Canada, Chile, China, India, Japan, the Republic of Korea, Mexico, the Philippines, Puerto Rico, Russia, Taiwan, and Turkey. The study began with the first participant’s first visit on November 19, 2020, and the data cutoff date was October 30, 2023, when all participants had either completed the study up to week 54 or had terminated the study before week 54.

All participants were 18 years or older, had a hemoglobin A_1c of 12% or less, had a diagnosis of diabetes type 1 or 2, and had PDR in the study eye with no evidence of previously taking PRP. If 2 eyes were eligible, the eye with the worse visual acuity was used as the study eye. Participants were randomized 1:1 to receive either brolucizumab in a 6-mg dose or PRP. Patients who received brolucizumab had received 3 doses every 6 weeks and then received the remaining doses every 12 weeks. PRP was administered in 1 to 4 sessions up to week 12.

Change in best corrected visual acuity (BCVA) at week 54 was the primary end point of the study. Proportion of participants with no PDR, proportion of participants with center-involved diabetic macular edema up to week 54, proportion of study eyes developing vision-threatening complications, and change from baseline in Early Treatment Diabetic Retinopathy Study (ETDRS) Diabetic Retinopathy Severity Score (DRSS) level at week 54 were the secondary end points.

There were 689 participants who were included in the study, of whom 347 received brolucizumab. There were 572 participants who completed the week 54 visit. The mean (SD) age of patients was 53.9 (11.39) years, and 40.1% of the participants were women. The mean BCVA at baseline was 77.1 (10.55) letters.

The researchers found that the primary objective of the study was met, with a letter score change of 0.2 (0.72) in the brolucizumab arm vs –4.2 (0.73) in the PRP arm. Change in disease severity was better with brolucizumab compared with PRP. The brolucizumab arm had an increase in patients with no PDR, from 56 patients at baseline to 187 patients at week 54; the PRP arm had an increase of 45 patients at baseline to 65 patients at week 54. Patients on brolucizumab had a lower proportion of patients reporting a center-involved diabetic macular edema event (31.1% vs 72.7%).

Patients using brolucizumab were more likely to have a 2-step or greater improvement in ETDRS compared with those in the PRP arm at week 54 (45.4% vs 20.4%). Ocular adverse events were more common in the PRP arm (49.1% vs 34.3%) and serious adverse events were more common in the PRP arm as well (6.4% vs 2.9%).

There were some limitations to this study. Although the researchers aimed to enroll patients without diabetic macular edema, a review by the central reading center found that 41.3% of patients had a central subfield thickness of 280 μm or higher at screening. The threshold for center-involved diabetic macular edema confirmation was lower in this study than in other clinical trials. A minority of patients did not have confirmed PDR.

The authors concluded that this trial showed superior outcomes with brolucizumab compared with PRP, with future results providing more information on the finding.

“These findings suggest that brolucizumab provides effective disease control in PDR by reversing disease progression and maintaining functional vision through the prevention of [vision-threatening complications],” the researchers wrote. “Brolucizumab may be a viable treatment alternative to PRP for patients with PDR.”

References

1. Wolf S, Chen Y, Li X, et al. Brolucizumab in the treatment of proliferative diabetic retinopathy: the CONDOR randomized clinical trial. JAMA Ophthalmol. Published online April 23, 2026. doi:10.1001/jamaophthalmol.2026.1008
2. Gullapalli V. Panretinal photocoagulation. Eyewiki. January 7, 2026. Accessed May 5, 2026. https://eyewiki.org/Panretinal_Photocoagulation